JPH0777295B2 - Double-sided circuit connection method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a double-sided circuit connecting method for connecting circuits formed on both sides of a substrate.

2. Description of the Related Art Conventionally, as a connection method for connecting circuits formed on both sides of a board, as shown in FIG. 4, a square pin 13 is fitted into a through-hole 12 formed in the board 11, Solder 15 between both ends of the square pin 13 and lands 14 connected to the circuits on both sides of the board 11.
A method of connecting is known. Further, as shown in FIG. 5, a pair of holes 16a and 16b are formed in the substrate 11, a jumper wire 17 is inserted between the pair of holes, and the land 14 and the jumper wire 17 on both sides of the substrate 11 are dipped. A method of connecting with solder 18 or solder 19 with a soldering iron is also known.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, the connection method using the square pins 13 is different between the square pins 13 and the solder 15 due to the difference in thermal expansion between the board 11 and the square pins 13.
There is a problem that cracks are likely to occur between the land 15 and the land 14 or between the land 14 and the substrate 11. In addition, the method using the jumper wire 17 has a problem that a large space is required because the pair of holes 16a and 16b are formed at intervals, and further, the solder 18, due to the difference in thermal expansion between the substrate 11 and the jumper wire 17, There is a problem that cracks occur in 19 or relative movement of the jumper wire 17 causes relative movement to the joint surface with the solders 18 and 19, resulting in poor conduction between the jumper wire 17 and the solders 18 and 19. .

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a method capable of connecting circuits on both surfaces of a substrate without being affected by a difference in thermal expansion.

Means for Solving the Problems In order to achieve the above object, the present invention forms a single through hole penetrating through a substrate having circuits formed on both sides, and A land for connection is formed on the periphery, a U-shaped jumper wire held by an insertion jig is inserted into the through hole, and the head of the jumper wire protruding from the through hole is pressed and repaired. Characterized in that a bent portion is formed so as to be self-held in the through hole by being pressed by a tool and bent in a perspective direction with respect to the inner peripheral surface of the through hole, and the jumper wire is connected to the land by a conductor. To do.

Effects Since the present invention has the above-described configuration, it is sufficient to form a single through hole in the substrate, a small space is required, and a jumper wire is inserted into the through hole to self-hold the work, and the jumper wire is also easy. Since the bent line is formed on the substrate, the difference in thermal expansion between the substrate and the jumper wire can be absorbed by the bent portion, and cracks do not occur at the connecting portion between the jumper wire and the land.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

In FIG. 1 and FIG. 2, circuit wirings (not shown) are arranged on both sides of the substrate 1, and a single through hole 2 is formed in the substrate 1 at a position where these circuit wirings should be connected. ing. Connection lands 3a and 3b made of copper foil or the like are formed around both open ends of the through hole 2, and these lands 3a and 3b are connected to circuit wirings on both surfaces of the substrate 1, respectively. Then, the jumper wire 4 is inserted in the through hole 2.
Is inserted so as to be held in the through hole 2 by its own elasticity, and further, the jumper wire 4 is formed with a bent portion 5 that is bent in a perspective direction with respect to the inner peripheral surface of the through hole 2. . Further, as shown in FIG. 2, both ends of the jumper wire 4 are connected to the lands 3a and 3b by solder 6, respectively.

Next, the connection method will be described. As shown in FIG. 1, the jumper wire 4 is inserted into the through hole 2 of the substrate 1 in which the through hole 2 and the lands 3a and 3b are formed at predetermined positions in advance. A specific method of inserting the jumper wire 4 will be described with reference to FIG. 3. First, as shown in FIG. 3A, the lower end portion of the jumper wire 4 cut into a predetermined length and formed into an inverted U shape is cut off. It is held by the insertion jig 7 and inserted into the through hole 2 of the substrate 1 from below, and then the upper end of the jumper wire 4 is appropriately spaced above the substrate 1 as shown in FIG. The pressing jig 8 placed in the open position is brought into contact with and received, and the insertion jig 7 is further pushed up to spread the lower end portion of the jumper wire 4 to both sides to engage with the lower surface of the substrate 1, and finally the third jig. As shown in FIG. 3C, the holding jig 8 is lowered toward the upper surface of the substrate 1 to deform the intermediate portion of the jumper wire 4 so as to spread it to both sides to form a bent portion 5. The bent portion 5 of the jumper wire 4 elastically pushes the inner peripheral surface of the through hole 2. To be in. In this way, the jumper wire 4 is inserted into the through hole 2 and self-held, and then both ends of the jumper wire 4 are landed as shown in FIG.
The connection is completed by connecting 3a and 3b with solder 6 and mechanically and electrically.

In the above connection state, when a difference in thermal expansion occurs between the substrate 1 and the jumper wire 4 such as when the substrate 1 becomes hot,
Since the bent portion 5 is formed in the jumper wire 4, the difference in thermal expansion is absorbed by elastically deforming the bent portion 5, and cracks do not occur in the connection portion or the like by the solder 6.

The present invention is not limited to the above embodiments. For example, the specific shape of the jumper wire 4 is not limited to the example shown in the drawings, and as described in the claims, the inner peripheral surface of the through hole 2 is elastically pressed to penetrate the through hole 2. The same effect as that of the above-described embodiment can be obtained as long as it has a bent portion 5 that can be self-held inside and that is bent in the perspective direction with respect to the inner peripheral surface of the through hole 2. Further, the specific insertion method of the jumper wire 4 can be arbitrarily changed and implemented. In addition to the solder 6, a conductive adhesive or the like can be used to connect the lands 3a and 3b to the jumper wire 4.

EFFECTS OF THE INVENTION According to the double-sided circuit connection method of the present invention, a jumper wire is inserted into a single through hole formed in a substrate and both ends thereof are connected to a land, so that the connection work is simple,
Further, since it is only necessary to form a single through hole, the required space can be small, and since a jumper wire is used, the cost is low. Moreover, since the jumper wire has a bent portion, the difference in thermal expansion between the substrate and the jumper wire can be absorbed by the deformation of the jumper wire, and there is no risk of causing a connection defect due to the occurrence of cracks, etc. It is possible to provide a high connection method.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a vertical sectional front view showing a state in which a jumper wire is inserted in a substrate, FIG. 2 is a vertical sectional front view in a connected state, and FIG. ), (B),
(C) is a vertical sectional front view of the process of inserting the jumper wire into the through hole, and FIGS. 4 and 5 are vertical sectional front views of a conventional example. 1 ... Substrate 2 ... Through holes 3a, 3b ... Land 4 ... Jumper wire 5 ... Bent part 6 ... Solder

Claims (1)

[Claims] 1. A substrate having circuits formed on both sides thereof is provided with a single through hole penetrating the circuit, and connecting lands are formed around the open ends of both sides of the substrate of the through hole. The U-shaped jumper wire held by the insertion jig is inserted therein, and further, the head of the jumper wire protruding from the through hole is pressed by the holding jig so as to be self-held in the through hole. A double-sided circuit connecting method is characterized in that a bent portion that bends in a perspective direction is formed with respect to the inner peripheral surface of the through hole, and the jumper wire is connected to the land by a conductor.